I agree with aki in all points.

This wall really needs improvement. The first what you should do is cleaning the scan or finding a bigger one or vectoring it if you like. The quality now is blurry and grainy which is not good. Also his right hand looks weird. It looks like you have cut to much of it by extracting the scan. I also suggest to get rid of the glowing effect around him or behind him. It doesn't look very good.

The background is very plain and boring. At the moment you only have a solid black background with some strange circles with a gradient. That's not really enough.

I don't really know what sort of texture you used but it doesn't work good with the wall. Maybe you need to blend it in more or lower the opacity. You should also use another font for the text. Looks somehow strange.